1. Field of the Invention
The present invention relates to a guide device for guiding an endless torque-transmitting means. The guide device includes at least two corresponding guide tongues, between which the endless torque-transmitting means is at least partially guided, the guide tongues being held at a predetermined distance from each other by means of a connection region. The invention also relates to a mold for producing a guide device for an endless torque-transmitting means, and including two corresponding mold halves.
2. Description of the Related Art
A guide device is known in the automotive engineering field for guiding or receiving an endless torque-transmitting means for a transmission, in particular for a belt-driven conical-pulley transmission (CVT transmission). In the belt-driven conical-pulley transmission the endless torque-transmitting means is used to transmit torque between two pairs of pulleys, the endless torque-transmitting means being, for example, a chain or a belt. To fulfill desired acoustic requirements it is necessary to reduce the so-called strand vibrations of the endless torque-transmitting means, in order thereby also to lower the noise level. For that purpose, a receiving rail is provided as a guide device to partially receive the endless torque-transmitting means. The receiving rail includes corresponding tongues, between which the endless torque-transmitting means is guided.
It has been found that the dimensions of a chain-receiving guide channel formed between the two corresponding tongues can change due to temperature fluctuations. As a result, it is possible for too large a play to occur between the endless torque-transmitting means and the guide surfaces of the chain-receiving channel, so that the latter can no longer reduce the strand vibrations adequately. Hence the acoustical requirements are no longer fulfilled. In particular, at low temperatures jamming of the endless torque-transmitting means can occur, and thus undesired high wear.
Thus, an object of the present invention is to provide a guide device of the type identified above that is designed so that the distance between the guide tongues can be held substantially constant, independent of temperature fluctuations.